In an electrical junction box such as a junction box to be mounted on a motor vehicle, internal circuit members such as bus bars and a printed board are contained at a high density on account of rapid increase of electrical and electronic components. Relays and electronic components are mounted on the printed board.
For example, JP 2006-187052 A (Patent Document 1) discloses an electrical junction box in which a number of relays are mounted on a printed board contained in a casing and an electrical power source bus bar is directly connected to the relays.